Saturday, November 29, 2008

VO2 the Max

Last Tuesday I did a VO2 max test.

I was recruited by Jordan Guenette at the Health & Integrative Physiology Laboratory at UBC. This is actually a two-party study, which I will be completing next Tuesday. To help explain what this study is about I asked Jordan for a brief explanation in not-too sciency terms. Here is what he had to say:

Recent evidence suggests that elite female cyclists may be more susceptible to certain respiratory limitations during exercise relative to male cyclists. These limitations cause women to have a different breathing response to exercise which can put the primary respiratory muscle (the diaphragm) under more stress during exercise. The greater stressed experienced by the diaphragm might make it more susceptible to fatigue. Therefore, the purpose of this study is to directly measure the force production of the diaphragm in response to exercise and determine if females experience more diaphragm fatigue than males.

Sounds good to me.

So with the incentive to get some solid test numbers out of it both now and again when I'm in peak race form in July, I happily agreed to help out.

Day one involved acquiring some basic physical information such as height & weight (182 cm & 67kg - and hazel eyes for all you single ladies out there...). We then did some breathing tests to make sure I wasn't lying about not having asthma or Pneumonia or the Black Lung or something like that. The first one measured my lung capacity (among other things) and it turns out I'm right around average with 5.5L max volume. The other tests involved measuring "maximal inspirations and expirations". I won't go into detail (because I'm not smart enough) but to give you an idea of things for the inspirations, imagine wrapping about thirty layers of plastic wrap over your mouth and then poking a pinhole in it so you can breath in...as hard as you can. With your nose plugged. That's sort of it except I had a handy little mouth piece that was easily removable:

I was at this point also introduced to this interesting little fellow:

I'll go into more detail about what this device does in my follow up post as it will be used more during the second half but I'll tell you now that it's quite stimulating...

After these tests were over, Jordan strapped the headgear on for the VO2 test. For ten minutes I had to wear it while at rest. Jordan gave me a book to read to pass the time, which by chance, is the same book I just started reading at home.

Once the ten minutes were up it was time to get on the bike. I was given some time to warm up and then we started the test. The way it worked was by Jordan starting the bike at 200W resistance and then upping it by 30W every three minutes. Easy enough to start.

Every few minutes Jordan would come over with a clip board that effectively had a rating describing how my legs & lungs were feeling as time progressed. I would simply tap on each descriptor for each element. I wasn't feeling amazing on this day so things were getting around a 4/10 to start with.

Three minutes goes by - 230W. No promlem.Three more minutes go by - 260W. Easy enough.Three more minutes go by - 290W. This is where things start to suck. Probably at around a 6-7/10:

Three more minutes go by - 320W. This is where things really start to suck...but I survived. Around an 8/10.Three more minutes go by - 350W. This is where things REALLY start to suck...and I fail. I couldn't even accuratly tap on the clipboard anymore. Jordan was great at encouraging me to push as hard as I could but eventually the cadence dropped below 60rpm and that's when it's all over.

Now, I've become accustom to hurting myself and pushing limits on a bike. I do this several times a week nowadays. I have experienced nausea, stitches, legs that scream to stop and lungs that do the same. I'm pretty used to it. However, after this test I came across a new one. Blurry vision. Maybe it was just the sweat in my eyes but I had a hard time focusing on much for a minute or two after it was all over...and I felt a bit pukey so I feel that I can at least say I gave Jordan a good effort. Here's what these sensations look like:

It gives you an idea. Although, I wasn't about to keep the headgear full of slobber on once I was done for a photo op so this is the best I have to show.

With the worst now over I spent the next few minutes regaining my breath and vision and doing an easy spin to cool down. Shortly thereafter, endorphins kicked in and I felt pretty good.

LEGEND VE = minute ventilation (amount of air you breathe in and out per minute) VO2 = Oxygen consumption VCO2 = Carbon Dioxide production RER = Respiratory Exchange ratio which is calculated by taking VCO2 and dividing it by VO2

Not bad...could use some work (particularly the formatting for viewing).

Stay tuned for my follow up post. I'll describe the experience of having a couple of catheters inserted into my esophagus and stomach via my nose, what that ring thing is for and how I do riding at 90% of maximum exertion for as long as physically possible.